Did you check the binding is IIS? (inetmgr.exe) It may not be registered to accept all hostnames on 8080.
For example, if you set it up for mysite.com:8080 and hit it at localhost:8080, IIS will get the request but not have a hostname binding to match so it rejects.
Outside of that, you should check the IIS logs (C:\inetpub\logs\wmsvc#) on the server and see if you are seeing your request. Then you’ll know if its a problem on your client or on the server itself.